cos2θ=根号2/3,则sin^4θ+cos^4θ=
cos2θ=根号2/3,则sin^4θ+cos^4θ=
已知cos2θ=根号2/3,则 sin^4θ+cos^4θ的值为________.
1.已知cos2θ=根号2/3,则sin^4+cos^4的值为________.
2sinθ+cosθ/sinθ-3cosθ=-5,求cos2θ+4sinθ
已知sinθ/2+cosθ/2=2根号3/5,则sinθ= ,cos2θ=
若cos2θ=√2/3,则sinθ^4+cos^4的值为
cos2θ=√2/3,则cos^4-sin^4的值为
已知sinθ+cosθ=2sinα,sinθcosθ=(sinβ)^2,求证4(cos2α)^2=(cos2β)^2
求证cos^4θ-sin^4θ=cos2θ
已知θ为第二象限角,sinθ+cosθ=根号3/3,则cos2θ=
cos2α/[sin(α-π/4)]=-根号2 /2,cosα+sinα=?
已知cos2θ=3/5,求sin∧4θ+cos∧4θ